Crystal holder



March 3% 1948 ug s-n gg g 2,438,708

CRYSTAL HOLDER Filed Sept. 3.4,,

Patented Mar. 30, 1948 UNITED STATES PATENT OFFlCE cnYsTAL HGLDER Walter E. Kuenstler, Clifiside Park, N. .i. Application September 1d, 1945, Serial No. 616,287

' 13 claims. (Cl. 171-827) This invention relates to crystals of the character used for radio purposes, such as crystals of quartz, tourmaline, or other piezo=electric mineral, and one of the objects of the invention is to provide an improved enclosing and mounting means for crystals of this character.

The mounting and enclosing of crystals, as practiced at the present time, is often such that the crystal is subjected to the efiects oi vibration, dust and dirt, climatic conditions including dampness and other factors, all of which tend to create deficiencies in operation, raise or lower the natural frequencies of the crystals, and in some cases, render the crystals completely inoperative.

The present invention contemplates the provision of means for mounting and housing a crystal, wherein the crystal and its associated parts may be quickly and accurately assembled and may be permanently enclosed or encased in a protective moulded material, the latter constituting an enclosing covering completely'and effectively protecting the crystal and its connections, whereby permanence of relationship of the enclosed parts is assured as well as complete and lasting protection against climatic conditions, moisture, vibration and other factors normally injurious or destructive to crystals of conventional construction. A

These and other objects are attained by the structure hereinafter described and more particularly set forth in the claims appended hereto.

In the accompanying drawing, wherein an 11- lustrative embodiment of the invention is disclosed, Fig. 1 is a horizontal sectional view through the crystal casing, with a portion of oneof the cover members shown fragmentarily; Fig. 2 is a face viewof the frame of insulating material extending around the edges of the crystal and electrodes; Fig. 3 is a face view of the complete crystal and bolder enclosed in an insulating covering; Fig. 4 is an edge view of the crystal and its enclosing means, the insulating covering thereover being indicated in dot-and-dash lines; Fig. 5 is a sectional view on the line 5-5 of Fig. 1, looking in the direction of the arrows; Fig. 6 is a view looking at the open side of one of the metallic cover members; Fig. 7 is a transverse sectional view through the cover member shown in Fig. 6, and Fig. 8 is an end view of the frame of Fig. 2.'

In the embodiment of theinvention shown in 2 spectlvely at 2 and 3. The crystal can also be of the so-called plated" type, wherein metallic electrode surfaces are provided on the opposite faces of the crystal by means oi a thin metallic coating or plating applied to each oi said faces. Thus, when herein referring to "electrodes I wish to be understood as meaning either the plated coatings applied to the faces of the crystal, or to the separate metallic plates between which, the crystal is positioned, as indicated in Fig. 5.

The crystal and its electrodes, of either the plated type or the metallic separate plate type, are located within the central aperture 5 or a frame 4 of insulating material. I! desired, the inner wall surfaces of the frame surrounding the aperture 5, may be provided with the projecting ribs 8, shown dotted in Fig. 2, for holding the crystal and electrodes centered and properly spaced from the sides of the aperture 5.

The frame 4, within which the crystal and electrodes are contained, is sandwiched between a pair of plate-like metalic cover members i and 8 with which the electrodes 2 and 3 respectively, establish electrical contact. Thetwo cover members i and 8 are of like shape and construction, each being of cup-shape formation, and being provided with the base wall 12 and the upstanding side walls ll. One oi. the side walls of each of the cover members is provided with an integrally-formed, laterally-extending lug l8. When the two cover members are placed in position wlth the frame 4 located between them, the two lugs extend in opposite directions, as clearly seen in Fig. 4, for soldering or other attachment to suitable terminals in the circuit of which the crystal forms a part.

Frame 4 is of such thickness that when it is positioned between the two cover members! and 8, it holds said cover members apart or in spaced relation and acts as an insulating separator between said cover members. As will be observed in Figs. 2 and 8, the opposite side walls of the frame 4 are each provided with a pair of depressions or indentations 9 into which wall portions I 0 on the walls ll of the cover members 1 and 8 are indented or depressed, thereby forming a. locking engagement between the cover members I and 8 and the frame 4. This arrangement is such as to provide a casing consisting of two spaced metallic cover members 1 and 8, between which is secured the frame 4, the latter constituting a separator between the cover members and providing an aperture 5 in which the crystal and electrodes are located.

Located within the enclosure thus constructed, is an arched plate spring I30, that'is situated between the cover member 8 and the electrode 3, said plate spring I30 acting to urge the crystal and electrodes toward the cover member 1 to cause the electrode to be pressed against the wall I2 of the cover member 1 to thereby establish electrical contact therewith. Said spring He also serves to establish electrical contact between the wall ii of the cover member 8 and the electrode 3. Thus, in the arrangement shown, electrical contact will be established between the electrodes and the cover members l and 8. If desired, the crystal and electrodes may be sandwiched between two plates by springs of the type shown at l3a, each of the springs in such a case, establishing contact with one of the cover members.

After the parts are assembled in the manner described, the resultant structure may then be encased in a suitable protective'coating or enclosing layer of insulating material, such as any one of the many plastic materials. having the desired characteristics. In the drawing, this applied coating is indicated at l5, Thecoating or covering l5 may be applied by being moulded about the assembly, or the assembly might be dipped while thecoating material is in plastic or fluid form, or a suitable coating might be sprayed over the assembly, the method of appliaction of the coating being largely dependent upon thenature of the material of which the coating is composed. The result will be that the crystal assembly, consisting of the crystal and electrodes, the frame 4 and the cover members I and 8, will be encased -or embedded in an enclosure of moulded insulaof the cover members 1 and 8 and as projecting substantially parallel to the plane of each of the cover members, it will be understood that said lugs might be attached in y other Suitable Way to the cover members and they might be positioned to project at an angle to the plane of said members, such changes being readily made without departing from the spirit of the invention.

In herein referring to the separate metallic plates 2 and 3 as electrodes I wish to be understood as meaning either suchseparate metallic plates 'or the plated surfaces or other metallic or conducting media disposed against or connected to the opposite faces of the crystal. It will also be understood that the container or casing herein disclosed'may be made in many diifer ent sizes and shapes, such changes being comprehended within the scope of the invention,

WhatIclaim is: g

1. A crystal holder comprising, a frame of insulating material provided with a central aperture, a crystal located within said aperture, a cupped metallic cover member extending over each face of the crystal whereby the frame and the crystal within the same are sandwiched between the cover members, said cover members constituting contact means by which the crystal may be connected into a circuit being-maintained in spaced relation by means of theframe interposed between them, one of the cover members being in electrical contact with a face of the crystal, and the second cover member beingin electrical contact with the second face of the crystal.

2. A crystal holder comprising, a substantially rectangular frame having a central aperture extending through it, plates fitted over the open sides of the aperture, a crystal and electrodes confined in the aperture between the plates, one of the electrodes being in electrical contact with one of the plates, the second electrode being in electrical contact with the second plate and flanges on the plates overlying parts of the frame and being attached to the frame to hold the plates'ln spaced relation with the frame interposed between them.

3. A crystal holder as provided for in claim.2, wherein the plates have side flanges extending completely around the sides of tlfe frame, the frame having recesses in its sides and the plates having their side flanges indented to engage in said recesses.

4. A crystal holder having a pair of cup-shaped metal plates, each having a laterally extended lug, a frame interposed between the plates and holding them in spaced relation, means on the plates for engaging the sides of the frame to hold the plates against displacement, the frame having a central aperture, and a crystal and electrodes in the aperture and-confined between the plates, one electrode being electrically connected to one of the plates and the other elec- 6. In a crystal holder as provided for in claim 5, wherein at least some of the side walls-of each plate has indentations, and the frame has indentations with which those on the walls engage '7. A crystal holder comprising, a frame of insulating' material provided with an aperture extending through it, a crystal located in said aperture, a cupped metallic cover member extending over each face of the frame whereby the frame and the crystal within the same are sandwiched between the cover members, the frame being indented and the cover membershaving indented portions engaging with the indentations in the frame to thereby secure the cover members to the frame, said cover members being maintained in spaced relation by means of the frame interposed between them, one of the cover members being electrically connected to a face of the crystal and the second cover member being electrically connected to the second face of the crystal.

8. A crystal holder having a pair of cup-shaped metal cover members, a frame of insulating material located between said members and holdin them in spaced relation, each cover member-being provided with a projecting contact member, the frame having a central aperture, a crystal and electrodes located in said aperture between the cover members, one electrode being electrically connected with one of the cover members and the second electrode being electricallyv connected with the second cover member.

9. A crystal holder having a pair of cupshaped metal cover members, a frame of insulating material located between said members and holding them in spaced relation, said cover member being provided with a projecting contact member, the frame having a central aperture, a crystal and electrodes located in said aperture between the cover members, one electrode being zlectrically connected with one of the cover members and the second electrode being electrically connected with the second cover member, and an insulating coating applied completely about the cover members and the frame, the contact members protruding out of the insulating coating.

10. A crystal holder comprising, a crystal and electrodes, a frame of insulating material extending around the edges of the crystal and electrodes, a pair of spaced metallic plates between which the frame is sandwiched, means for urging the crystal and electrodes in a direction to cause an electrical contact between one of the electrodes and one of the plates, said means establishing an electrical contact between the second electrode and the second plate, and means on the plates constituting contact members by which the crystal can be connected in a circuit.

11. A crystal holder comprising, a crystal and electrodes, a frame of insulating material extending around the edges of the crystal and electrodes, a pair of spaced metallic plates constituting contact members by which the crystal can be connected in a circuit, the frame being sandwiched between said plates whereby the crystal and electrodes are confined between the plates, means for urging the crystal and electrodes in a direction to cause an electrical contact between one of the electrodes and one of the plates, said means establishing an electrical contact between the second electrode and the second plate, and means for securing the plates to the frame, the frame acting as a spacer between the plates and holding the same in spaced relation.

12. A crystal holder comprising, a crystal and electrodes, 9, frame of insulating material extending around the edges of the crystal and electrodes, a pair of spaced metallic plates having projections constituting contact members by which the crystal can be connected into a circuit. the frame being sandwiched between said plates whereby the crystal and electrodes are confined between the plates, means for urging the crystal and electrodes in a direction to cause an electrical contact between one of the electrodes and one of the plates, said means establishing an electrical contact between the second electrode and the second plate, and means for securing the plates to the frame, the frame acting as a spacer between the plates and holding the same in spaced relation, the projections on the plates being in the form of tongues extending laterally from the plates.

13. A crystal holder comprising, a crystal and electrodes, a frame of insulating material extending around the edges of the crystal and electrodes, a pair of spaced metallic plates constitut il'ig contact members by which the crystal can be connected into a circuit, the frame being sandwiched between said plates whereby the crystal and electrodes are confined between the plates, means for urging the crystal and electrodes in a direction to cause an electrical contact between one of the electrodes and one of the plates, said means establishing an electrical contact between the second electrode and the second plate, means for securing the plates to the frame, the frame acting as a spacer between the plates and holding the same in spaced relation, each of the plates being substantially cup-shaped, the frame fitting within the plates, each of the plates being provided with a lateral extension constituting a, contact member, and an insulating coating enclosing the plates and frame, the contact members protruding through and out of the insulating coating.

WALTER E. KUENSTLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITE]? STATES PATENTS Number Name Date 1,800,576 Tagner Apr. 14, 1931 1,922,032 Ehbert et a1 Aug. 15, 1933 2,045,403 Nicholides June 23, 1936 2,324,024 Reom July 13, 1943 

